This invention relates to a component selector assembly and more particularly, to an assembly which pseudo-randomly selects components and which causes the selected components to selectively and cooperatively generate a signal.
It is often desirable to pseudo-randomly select signal generating components or elements, such as transistors, in order to substantially prevent or reduce the correlation between the identity of the selected components or elements and the value of the selection signal (e.g. in order to prevent the same signal generating elements from being selectively activated each time or substantially each time that the selection signal is of a certain value).
This correlation is particularly undesirable, for example and without limitation, in digital-to-analog converters. That is, these converters typically receive data, such as xe2x80x9cthermometer type dataxe2x80x9d, which represents a certain value and which is used to energize one or more selectively energizable components and/or elements, thereby allowing and/or causing the selected elements and/or components to cooperatively provide an analog output signal. Since the signal generating components and/or elements are not exactly identical and/or are xe2x80x9cmismatchedxe2x80x9d, if the same components and/or elements are energized each time that the received data (e.g., the thermometer type data) is of a certain value, distortion is created within the converter, (e.g. the thermometer data is xe2x80x9ccorrelatedxe2x80x9d with the selectively energizable components or elements), thereby causing an undesirable and inaccurate output signal.
There is therefore a need to pseudo-randomly select the selectively energizable components or elements in an efficient and cost effective manner, thereby decreasing and/or substantially eliminating the correlation between the received input data and the identity of the signal producing elements or components which are activated in response to the received data.
It is a first object of the invention to provide a method and an apparatus for selecting signal generating components and/or selectively energizable elements which overcomes some or all of the previously delineated drawbacks of such prior methods, techniques, and/or apparatuses.
It is a second object of the invention to provide a method and an apparatus for pseudo-randomly selecting signal generating components and/or elements which overcomes some or all of the previously delineated drawbacks of such prior methods, techniques, and/or apparatuses and which is accomplished in a relatively cost efficient manner.
It is a third object of the invention to provide a digital-to-analog converter which has substantially less distortion than prior digital-to-analog converters.
According to a first aspect of the present invention, an apparatus for use in combination with data is provided. The apparatus includes several selectively activated signal generating elements; and a randomizer which receives the data and which is coupled to the several selectively activated signal generating elements, which splits the data into at least a first and a second portion, and which utilizes the first portion to pseudo-randomly select at least one of the several selectively activated signal generating elements and which utilizes the second portion to pseudo-randomly select at least a second one of the several selectively activated signal generating elements.
According to a second aspect of the present invention a method for selecting signal generating elements is provided. The method includes the steps of placing each of the signal generating elements into one of two groups; and pseudo-randomly selecting a first of the signal generating elements from a first of the two groups and pseudo-randomly selecting a second of the signal generating elements from a second of the two groups.
These and other aspects, features, and advantages of the present invention will become apparent from a reading of the following detailed description of the preferred embodiment of the invention and by reference to the following drawings.